/*******************************************************************************
 * Copyright (c) 2000, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * Contributors:
 * IBM Corporation - initial API and implementation
 * Sebastian Davids <sdavids@gmx.de> - Collapse all action
 * Sebastian Davids <sdavids@gmx.de> - Images for menu items
 *******************************************************************************/
package cn.elwy.rcp.ui.navigator.internal.resources.actions;

import java.net.URL;
import java.util.Collections;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.MenuManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.actions.ExportResourcesAction;
import org.eclipse.ui.actions.ImportResourcesAction;
import org.eclipse.ui.navigator.CommonActionProvider;
import org.eclipse.ui.navigator.ICommonActionExtensionSite;
import org.eclipse.ui.navigator.ICommonMenuConstants;
import org.eclipse.ui.navigator.ICommonViewerWorkbenchSite;
import org.eclipse.ui.navigator.WizardActionGroup;

import cn.elwy.rcp.ui.navigator.internal.resources.plugin.WorkbenchNavigatorMessages;
import cn.elwy.rcp.ui.navigator.internal.resources.plugin.WorkbenchNavigatorPlugin;

/**
 * Adds actions for Import/Export wizards. The group is smart, in that it will either add actions for Import and Export,
 * or if there are context sensitive options available (as defined by <b>org.eclipse.ui.navigator.commonWizard</b>),
 * then it will compound these options into a submenu with the appropriate lead text ("Import" or "Export").
 * <p>
 * <strong>EXPERIMENTAL</strong>. This class or interface has been added as part of a work in progress. There is a
 * guarantee neither that this API will work nor that it will remain the same. Please do not use this API without
 * consulting with the Platform/UI team.
 * </p>
 * 
 * @since 3.2
 */
public class PortingActionProvider extends CommonActionProvider {

  private static final String COMMON_NAVIGATOR_IMPORT_MENU = "common.import.menu"; //$NON-NLS-1$

  private static final String COMMON_NAVIGATOR_EXPORT_MENU = "common.export.menu"; //$NON-NLS-1$	

  private ImportResourcesAction importAction;

  private ExportResourcesAction exportAction;

  private WizardActionGroup importWizardActionGroup;

  private WizardActionGroup exportWizardActionGroup;

  private boolean disposed = false;

  private boolean contribute = false;

  public void init(ICommonActionExtensionSite anExtensionSite) {

    Assert.isTrue(!disposed);

    if (anExtensionSite.getViewSite() instanceof ICommonViewerWorkbenchSite) {

      IWorkbenchWindow window = ((ICommonViewerWorkbenchSite) anExtensionSite.getViewSite()).getWorkbenchWindow();
      importAction = new ImportResourcesAction(window);
      exportAction = new ExportResourcesAction(window);
      importWizardActionGroup = new WizardActionGroup(window, PlatformUI.getWorkbench().getImportWizardRegistry(),
          WizardActionGroup.TYPE_IMPORT, anExtensionSite.getContentService());
      exportWizardActionGroup = new WizardActionGroup(window, PlatformUI.getWorkbench().getExportWizardRegistry(),
          WizardActionGroup.TYPE_EXPORT, anExtensionSite.getContentService());
      contribute = true;
    }
  }

  /**
   * Extends the superclass implementation to dispose the subgroups.
   */
  public void dispose() {
    if (!contribute) {
      return;
    }
    importWizardActionGroup.dispose();
    exportWizardActionGroup.dispose();
    importAction = null;
    exportAction = null;
    disposed = true;
  }

  public void fillContextMenu(IMenuManager aMenu) {
    if (!contribute) {
      return;
    }

    Assert.isTrue(!disposed);

    ISelection selection = getContext().getSelection();
    if (!(selection instanceof IStructuredSelection) || ((IStructuredSelection) selection).size() > 1) {
      addSimplePortingMenus(aMenu);
    } else {
      addImportMenu(aMenu);
      addExportMenu(aMenu);
    }
  }

  /**
   * Returns the image descriptor with the given relative path.
   */
  protected ImageDescriptor getImageDescriptor(String relativePath) {
    String iconPath = "icons/full/"; //$NON-NLS-1$ 
    URL url = FileLocator.find(WorkbenchNavigatorPlugin.getDefault().getBundle(), new Path(iconPath + relativePath),
        Collections.EMPTY_MAP);
    if (url == null) {
      return ImageDescriptor.getMissingImageDescriptor();
    }
    return ImageDescriptor.createFromURL(url);
  }

  private void addSimplePortingMenus(IMenuManager aMenu) {
    aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, importAction);
    aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, exportAction);
  }

  private void addImportMenu(IMenuManager aMenu) {

    importWizardActionGroup.setContext(getContext());
    if (importWizardActionGroup.getWizardActionIds().length == 0) {
      aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, importAction);
      return;
    }

    IMenuManager submenu = new MenuManager(WorkbenchNavigatorMessages.PortingActionProvider_ImportResourcesMenu_label,
        COMMON_NAVIGATOR_IMPORT_MENU);
    importWizardActionGroup.fillContextMenu(submenu);

    submenu.add(new Separator(ICommonMenuConstants.GROUP_ADDITIONS));
    submenu.add(new Separator());
    submenu.add(importAction);
    aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, submenu);
  }

  private void addExportMenu(IMenuManager aMenu) {

    exportWizardActionGroup.setContext(getContext());
    if (exportWizardActionGroup.getWizardActionIds().length == 0) {
      aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, exportAction);
      return;
    }
    IMenuManager submenu = new MenuManager(WorkbenchNavigatorMessages.PortingActionProvider_ExportResourcesMenu_label,
        COMMON_NAVIGATOR_EXPORT_MENU);
    exportWizardActionGroup.fillContextMenu(submenu);

    submenu.add(new Separator(ICommonMenuConstants.GROUP_ADDITIONS));
    submenu.add(new Separator());
    submenu.add(exportAction);
    aMenu.appendToGroup(ICommonMenuConstants.GROUP_PORT, submenu);
  }

}
